Honing device



July 3 l G. F. WAGSTAFF HONING DEVICE Filed Sept. 5, 1947 Patented July 3, 195i UNITED STATES PATENT OFFICE HONNG DEVICE Application September 5, 1947, Serial No. 772,450 In Great Britain September 9, 1946 13 Claims. 1

This invention relates to honing devices, that is to devices used for finishing components where a superlative finish is required and/or where the diameters have to be held to very fine limits. It is concerned with honing devices employed for finishing such components as pins, plug gauges, stub axles, shackle bolts or the like and referred to herein as external hones.

The main object of the invention is to provide a new or improved construction of external hone which is simple in construction and efficient in use. Another object is to provide a construction of external hone with which extremely fine adj ustment of the abrasive element may be obtained, such as is required for certain work, for example when a diamond stone is being employed.

A further object is to provide improvements which enable the hone to be pre-set to produce work of the required finished diameter, the honing process being automatically discontinued when such diameter is obtained. Still further objects are to expedite the honing process, particularly during the initial roughing operation, to prevent damage to the abrasive element and to enable the latter to be readily inspected and changed as required.

The rst of these objects is achieved according to the invention by the provision of an external hone comprising two jaws pivoted together, one

at least of which carries an abrasive element adapted to bear against the surface of the work placed between the jaws, adjustment of the abrasive element relatively to said surface being effected by opening or closing the jaws` Preferably adjustment means, which may cornprise screw and nut mechanism, are associated with the jaws and maintain the latter in the posi@- tion to which they have been opened or closed by the operation of the adjustment means. The latter are preferably disposed beyond the abrasive element from the pivot in order to enable fine adjustment of the abrasive element.

According to another feature oi the invention one of the jaws near its free end has a table associated therewith the height of which relatively to a `contact portion of the other jaw may be adjusted, whereby honing of work placed between the jaws is automatically discontinued when said contact portion contacts the table to prevent further closing of the jaws.

Embodiments of the invention will now be d'escribed, by way of example, with reference to the accompanying drawings, in which- Figure 1 is a front elevation of one form of exi ternal hone according tothe invention,

Figure 2 is an end elevation of the hone, 1 v ,Figures 3 and 4 are sections on the lines 3-3 and 4&4 respectively of Fig-ure 1,

Figure 5 is a fragmentary front elevation of the lower jaw of the form of hone illustrated in Figure 1 showing a different abrasive element ar` rangement, and

Figures 6 and '7 are a fragmentary front elevan tion and end elevation respectively of the hone showing a preferred form of pre-setting arrange-- ment. y

The external hone illustrated in the drawings comprises two jaws Ill and I I gapped at one end to form knuckles i911, IIa receiving a hinge pin I'rby which the jaws are pivoted together, the jaws being of bowed form so that, with their free ends Ib, I Il) comparatively close together, the bowed portions dei-lne between them a substantially circular aperture I'Sl to accept the` work. The lower jaw I I is formed with an inwardly disposed slot i4 at or about the middle of its bowed portion to receive the abrasive element I5 in its holder IG which may be xedly mounted in the slot I4 by means of a set screw I'I.

The abrasive element I5 may be a natural stone or it may be artificially formed from any suitable abrasive compound, for example :a composition impregnated with diamond dust, compressed to block form. Two spaced guides I8, I8 arel preferably c'arried by the upper jaw Ill, the said guides being preferably formed by portions of a block I9 received in a slotI 2d in the upper jaw at or about the middlev of its bored portion and secured by means of a set screw ZI. As will be seen from Figure l, the guides I8 project into the substane tially circular aperture I3 to form guiding surfaces which bear upon a surface of revolution of work placed in contact therewith and with the abrasive element i5. The guides I3 bear at angularly spaced points against the surface of revolution of the work and, due to the fact that they are relatively xed and arranged at an angle to each other, they define a constant, tapering throat in which the work is held by the abrasive element I5. V n

As stated, the free ends l b, I Ib of the jaws are comparatively close together when the bowed portions define the substantially circular aperture I3, and these straight or unbowe'd free ends have screw mechanism arranged therebetween to keep theija'ws* It and II together in order to prevent damage to the abrasive' elementI ,I5I and also toy provide an adj-ustablesetting for the degree' of opening of thejaws about their pivotpiri I2. This screw mechanism comprises a; nut 22`in* the form of a trunnion block mounted in the end I Ib of the lower jaw which is bifurcated to receive the nut, as shown in Figures 3 and 4. The nut is retained by means of screws 23 the inner ends of which are formed with reduced pins 23a which serve as the trunnions upon which the nut 22 is pivotally mounted. A trunnion block 24 is similarly mounted in the end Ib of the upper jaw of the device and a long screw 25 passes through a clearance hole 26 in this trunnion block while its threaded end 2l screws into the nut 22. The upper end of the screw 25 is headed and knurled, as indicated at 28, to enable the screw to be manually operated to open and close the jaws I and I I. A compression coil spring 29 is mounted round the screw in abutment with the trunnion blocks 22 and 24, its ends being seated in shallow recesses 22a and 24a of the latter respectively, so that the jaws are always maintained in the position to which they have been set by the screw.

From the foregoing description it will be seen that the degree of opening or closing of the jaws I and I I about their pivot I2, and therefore the spacing between the abrasive element I5 and the guides I8, I8, is adjusted and set at a distance from the centre of movement, i. e. the centre of the pivot pin I2. Thereby very fine adjustment of the abrasive element is possible. In the example illustrated in the drawings the jaws are so dimensioned that the ratio of the spacing of the pivot centre from the vertical axis of the abrasive element and the centre line of the screw 25 respectively is approximately 1 :2.

In using the external hone described the screw 25 is slackened to enable the work to be inserted between the guides I8,*I8 and abrasive element I5 or, if required by the character or shape of the work, the screw may simply be completely screwed out of the nut 22 so that the jaws Ill and I I may be opened wide to enable them to be placed round the diameter to be honed. At the same time the required type of abrasive element, a roughing stone for example, may be placed in its holder in the lower jaw II. In this connection the arrangement of abrasive element and holder I6 illustrated in Figure 1 is suitable for use for the final polishing.. operation and for roughing if the work has-no initial ovality. Where ovality has to be removed in the roughing operation it is preierred to use the modiiied construction of holder and abrasive element arrangement shown in Figure 5. This holder Ia. is interchangeable with the holder I6 and has an enlarged head IGb in which two roughing stones I5a., I5a are set at an angle to each other, the holder being secured in the slot I4 of the jaw II by the set screw I'I in exactly the same manner as has already been described. With this arrangement each roughing stone I5a bears on the surface of the work at a point substantially diametrically opposite the lbearing point of one of the guides I8.

With the requisite type of abrasive element mounted in the jaw II, the screw 25 is replaced '(if it had previously been removed on account of the character or shape of the work as already mentioned) and screwed into the nut 22. During the initial roughing operation the screw 25 may be tightened down to apply pressure to the upper jaw I0 in order to speedup the process. Thereafter the roughing stone or stones may be replaced by a finishing or lapping stone until the operation is complete.

In a modied form of the device the screw mechanism may be pre-set to produce work of the required iinished diameter whereafter the honing process is automatically discontinued. Such an arrangement is illustrated in Figures 6 and 7 in which the screw mechanism comprises a nut 35 of substantial dimensions externally screwed at 3| and threaded into a tapped apertured 3Ia in the lower jaw II. A long screw 25a, of considerably smaller diam-eter than the nut passes through a clearance hole 26u, in the upper jaw ID and into the nut. The latter is headed to form a table 32, the height of which may be adjusted by r-otating the nut, and the free end Ib of the upper jaw is provided with upper and lower transverse ribs ille, Idd, the latter forming contact portions which rest on the table 32 and so determine the deer-ee of closing of the two jaws. The upper end of the long screw 25a in the upper jaw is headed and knurled at 23a as before to enable pressure to be put on the upper jaw by tightening the screw down on to the upper ribs IUC already described.

By splitting the lower jaw II vertically as indicated at 33 and providing a locking screw 34 or pinch bolt across the split portion it is possible to lock the table 32 in any position to which it is adjusted, this position being indicated by a graduated scale 35 around the periphery of the head of the nut which may be read against a stationary vertical blade or knife edge 36 attached to the lower jaw.

In -using this modified construction of external hone the nut 3i! is iirst adjusted to set the table 32 at the required height to give the finished dimension and looked in that position with the locking screw 34. rlhe honing process is carried out using roughing and/or polishing stones as already described, the operation being complete when upon turning the knurled head 28a of the screw 25a to tighten the latter the lower ribs Id contact the table top 32 of the n-ut 35 in the lower jaw II.

It will be understood that the ribs Ic, Id which are of rounded contour serve the same purpose, although in a more limited manner, as the trunnion mounting 23a of the construction shown in Figures l to 5. In this connection it may be remarked that the construction of the device shown in Figures 6 and '7 is intended to have a more limited range than the arrangement of Figures l to 5. The table top 32, in one sense, performs a similar function to the spring 29 of the iirst construction in that it maintains the jaws in the position to which they have been set.

The construction of external hone described may be held in the hand while the work is rotated within the substantially circular aperture I3 between the jaws. One of the jaws, however, preferably the lower jaw I I, may have an attachmeni-l by which it may be placed in the jawsof a chuck and rotated while the work is held stationary.

As already mentioned the slot I4 is adapted to receive interchangeable holders I6, Ia for the abrasive element or elements. A series of holders of either type may be provided which` are ci varying height or depth whereby the range of the device may be extended merely by exchanging holders. The same principle may be applied to the guide block I9 with further extension of the range of the hone as a result. An important feature of the hone according to the invention is that, due to the fact that the guides I8, I8 and abrasive element I5 are positively xed in the jaws, once they have been trued or aligned for work of any one diameter they remain true for all diameters within the range of the device,

Iclaim: A

1. A tool for honing external surfaces of revolution comprising in combination two jaws pivoted together towards one end to dene an aperture therebetween and having at least three spaced bearing portions adapted to bear unyieldingly at angularly spaced points upon a surface of revolution of a workpiece placed within said aperture between the jaws, two of said bearing portions being carried by one of said jaws so as to be relatively fixed and arranged at an angle to each other to define a throat in which the workpiece is held by another of said bearing portions carried by the other of said jaws, at least one of said bearing portions comprising an abrasive element, and means towards the other end of said jaws for closing the jaws about their pivot to, and positively holding them against opening movement from, any one of an infinite number of relative positions of adjustment to effect adjustment of the abrasive element relatively to at least one of said bearing portions.

2. A tool for honing external surfaces of revolution comprising in combination two jaws pivoted together towards one end to define an aperture therebetween, bearing means carried by one of said jaws to provide two spaced bearing surfaces fixed relatively to each other to form a constant outwardly narrowing throat between them, further bearing means carried by the other of said jaws and so disposed as to provide a third bearing surface spaced from said two relatively .fixed bearing surfaces, all three of said bearing surfaces being adapted to bear unyieldingly at angularly spaced points upon a surface of revolution of a workpiece placed within said aperture between the jaws and at least one of said bearing means comprising an abrasive element, and means towards the other end of said jaws for closing the jaws about their pivot to, and positively holding them against opening movement from, any one of an infinite number of relative positions of adjustment to effect adjustment of said'further bearing means relatively to said two relatively fixed bearing surfaces, said bearing means and said further bearing means being non-adjustable relatively to their respective jaws during the honing operation.

3. A tool for honing external surfaces of revolution comprising in combination two jaws pivoted together towards one end to dene an aperture therebetween, one of said jaws having two spaced non-abrasive bearing portions relatively fixed and arranged at an angle to each other to bear unyieldingly and substantially tangentially at angularly spaced points upon a surface of revolution of a workpiece placed within said aperture between the jaws, while the other of said jaws has a bearing portion comprising an abrasive element also adapted to bear unyieldingly and substantially tangentially upon said surface of revolution so that the workpiece is gripped at three points between said bearing portions, and means towards the other end of said jaws for closing the jaws about their pivot to, and positively holding them against opening movement from, any one of an infinite number of relative positions of adjustment to effect adjustment of the abrasive element relatively to said non-abrasive bearing portions.

4. A tool for honing external surfaces of revolution comprising in combination two jaws pivoted together towards one end to define an aperture therebetween, an abrasive element having a Fil flat bearing surface carried by one of said jaws, a non-abrasive guide having two relatively fixed flat bearing surfaces arranged at an angle to each other and carried by the other of said jaws, said abrasive element and non-abrasive guide projecting inwardly from said jaws and bearing unyieldingly with said at bearing surfaces at angularly spaced points upon a surface of revolution of a workpiece placed within said aperture between the jaws to grip the workpiece between said spaced points, and means towards the other end of said jaws for pivotally closing the jaws to, and positively holding them against opening movement from, any one of an infinite number of relative positions of adjustment to effect adjustment of the abrasive element relatively to said nonabrasive guide.

5. A tool for honing external surfaces of revolution comprising in combination two jaws pivoted together towards one end and spaced apart at the other end to define a workpiece-receiving aperture between the jaws, an abrasive element lixedly carried by one of said jaws, a non-abrasive guidexedly carried by the other of said jaws, said abrasive element and non-abrasive guide projecting into said aperture from said jaws to bear unyieldingly at three spaced points only upon a surface of revolution of a workpiece placed between the jaws, said non-abrasive guide bearing upon said surface of revolution at two angularly spaced and relatively fixed points .only while said abrasive element bears upon said surface of revolution at one point only angularly spaced from said two relatively fixed points and adjustable towards and away from said two relatively xed points by closing and opening movement of said jaws to adjustably grip the workpiece between said three spaced points, and means connecting the spaced apart ends of the jaws and operable to close the jaws about their pivot to, and positively hold them against opening movement from, any one of an innite number of relative positions of pivotal adjustment to eiect adjustment of the bearing point of said abrasive element relatively to the two relatively xed bearing points of said non-abrasive guide.

6. A tool for honing external surfaces of revolution comprising in combination two jaws pivoted together towards one end to define an aperture therebetween, a pair of abrasive elements carried in relatively spaced and xed relationship by one of said jaws and having flat bearing surfaces arranged at an angle to each other, a pair of non-abrasive guides carried in relatively spaced and xed relationship by the other of said jaws and having iiat bearing surfaces arranged at an angle to each other, said abrasive elements and non-abrasive guides projecting inwardly from said jaws and bearing unyieldingly on a surface of revolution of work placed within said aperture between the jaws at four spaced points, each of said abrasive elements bearing at a point substantially diametrically opposite the bearing point of one of said guides with respect to said surface of revolution, and means for closing the jaws to, and positively holding them against opening movement from, any one of an infinite number of relative positions of adjustment to effect adjustment of the abrasive elements relatively to said non-abrasive guides.

7. A tool for honing external surfaces of revolution comprising in combination two jaws associated towards one end for relative angular movement to define a variable aperture therebetween and having spaced bearing portions adapted to bear'unyieldingly at angularly spaced points upon a surface of revolution of a workpiece placed within said aperture between the jaws, at least one of said bearing portions comprising an abrasive element, means tending to resiliently hold the other end of said jaws open, and screw means towards said other end and operable to overcome said resilient means to close the jaws to, and positively hold them against opening movement from, any one of an innite number of relative positions of adjustment.

8. A tool for honing external surfaces of revolution comprising in combination two jaws pivoted together towards one end to define an aperture therebetween, an abrasive element xedly carried by one of said jaws, a non-abrasive guide xedly carried by the other of said jaws, said abrasive element and non-abrasive guide projecting inwardly from said jaws and bearing unyieldingly at at least three angularly spaced points upon a surface of revolution of a workpiece placed within said aperture between the jaws to grip the workpiece between said spaced points, screw and nut mechanism connecting said jaws and operable to pivotally close the jaws to, and positively hold them against opening movement from, any one of an infinite number of relative positions of adjustment to eiect adjustment of the abrasive element relatively to said nonabrasive guide, and a compression coil spring disposed around said screw with its ends abutting the jaws which are urged outwardly to the extent determined by the adjustment of said screw and nut mechanism.

9. A tool for honing external surfaces of revolution comprising in combination two jaws pivoted together towards one end to denne an aperture therebetween, an abrasive element xedly carried by one of said jaws, a non-abrasive guide xedly carried by the other of said jaws, said abrasive element and non-abrasive guide projecting inwardly from said jaws and bearing unyieldingly at at least three angularly spaced points upon a surface of revolution of a workpiece placed within said aperture between the jaws to grip the workpiece between said spaced points, a headed screw operatively connecting said jaws towards their other end, a member swivelly carried by one of said jaws and having a clearance hole through which said screw passes, and a nut swivelly mounted in the other of said jaws into which said screw is threaded to close the jaws about their pivot t0, and positively hold them against opening movement from, any one of an infinite number of relative positions of adjustment to effect adjustment of the abrasive element relatively to said non-abrasive guide.

10. A tool for honing external surfaces of revolution comprising in combination two jaws associated towards one end for relative angular movement to delinea variable aperture therebetween and having spaced bearing portions adapted to bear unyieldingly at angularly spaced points upon a surface of revolution of a workpiece placed within said aperture between thev jaws, at least one of said bearing portions comprising an abrasive element, screw means towards said other end and operable to close the jaws to, and positively hold them from opening movement from, any one of an innite number of relative positions of adjustment to effect adjustment of said abrasive element relatively to at least one of the other said bearing portions, and a member adjustably threaded upon said screw to determine the extent to which said screw may close the jaws.

11. A tool according to claim 4, wherein said means for closing the jaws to, and positively holding them against opening movement from, any one of an infinite number of relative positions of adjustment comprises screw mechanism connecting said other end of the jaws, a table screwed into one of said jaws so that its height may be adjusted to determine the moment of contact with the other of said jaws, and means to secure said table against rotation once it has been adjusted.

12. A tool according to claim 4, wherein said means for closing the jaws to, and positively holding them against Iopening movement from, any one of an innite number of relative positions of adjustment comprises screw mechanism connectling the free ends of 'said jaws, a split portion formed at the free end of one of said jaws, a table screwed into said split portion so that its height may be adjusted, screw means which bridge the split portion and are operable to free the table for rotation or clamp it against rotation from a position to which it has been adjusted, and a contact portion on the other of said jaws which contacts said table.

13. A tool according to claim 4, wherein said abrasive element is carried in a holder and said non-abrasive guide comprises a block, said holder and said block being removably mounted in slots transversely formed in the respective jaws, said slots forming xed seatings for said holder and said block.

GEORGE! FREDERICK WAGSTAFF.

REFERENCES CITED VThe following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,221,472 Rasmusen et al Apr. 3, 1917 1,346,271 Smith July 13, 1920 1,376,274 Hays et a1 Apr. 26, 1921 1,411,181 Peterson et al Mar. 28, 1922 Y 1,622,292 Reno Mar. 29, 1927 1,905,825 Egger et al Apr. 25, 1933 2,129,253 Willis Sept. 6, 1938 2,151,062 Wainscott Mar. 21, 1939 2,162,187 Tharp June 13, 1939 2,176,404 Landy Oct. 17, 1939 2,249,388 Kline July 15, 1941 

